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CENTAUREA cyanus 'Blue Boy'

Image of Centaurea cyanus 'Blue Boy'

Ernst Benary® Inc.

Family

Asteraceae

Botanical Name

CENTAUREA cyanus 'Blue Boy'

Plant Common Name

Batchelor's Buttons, Cornflower

General Description

Treasured for its sky-blue flowers that resemble small thistles, cornflower is a short-lived, cool-season annual from the northern temperate regions. The cultivar 'Blue Boy' has frilly double blooms on thigh-high stems sparsely furnished with narrow gray-green leaves. Fall-sown seedlings often overwinter as rosettes and flower the next spring. Plants bloom about 85 days after early-spring sowing.

Sow cornflowers in full sun and well-drained soil in early spring. In USDA zones 6 and warmer, seeds can also be sown in fall for winter or spring bloom. Remove spent flowers to prolong bloom time. Cornflower is a useful cutflower and a cottage garden favorite which often naturalizes. Combine it with other self-sowing annuals such as corn poppies and gloriosa daisies. The edible flowers make good decorations for salads and other foods.

Characteristics

  • AHS Heat Zone

    7 - 1

  • Sunset Zone

    H1, H2, 1a, 1b, 2a, 2b, 3a, 3b, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24

  • Plant Type

    Annual

  • Sun Exposure

    Full Sun

  • Height

    30"-36" / 76.2cm - 91.4cm

  • Width

    10"-15" / 25.4cm - 38.1cm

  • Bloom Time

    Indeterminate

  • Native To

    World/Pandemic, North America, Europe, Russia/Siberia, China, Korea

Growing Conditions

  • Soil pH

    Acidic, Neutral, Alkaline

  • Soil Drainage

    Well Drained

  • Soil type

    Loam, Sand

  • Tolerances

    Pollution, Drought

  • Growth Rate

    Very Fast

  • Water Requirements

    Average Water

  • Habit

    Upright/Erect

  • Seasonal Interest

    Spring, Summer, Fall, Winter

Ornamental Features

  • Flower Interest

    Showy

  • Flower Color

    Blue, Sky Blue

  • Foliage Color (Spring)

    Gray Green

  • Foliage Color (Summer)

    Gray Green

  • Foliage Color (Fall)

    Gray Green

  • Fragrant Flowers

    No

  • Fragrant Fruit

    No

  • Fragrant Foliage

    No

  • Bark or Stem Fragrant

    No

  • Flower Petal Number

    Single

  • Repeat Bloomer

    Yes

  • Showy Fruit

    No

  • Edible Fruit

    No

  • Showy Foliage

    No

  • Foliage Texture

    Medium

  • Foliage Sheen

    Matte

  • Evergreen

    No

  • Showy Bark

    No

Special Characteristics

  • Usage

    Cutflower, Mixed Border, Wildflower

  • Sharp or Has Thorns

    No

  • Invasive

    Sometimes

  • Attracts

    Butterflies

  • Self-Sowing

    Yes